16–102 The equilibrium constant for the reaction H 2
at 1 atm and 1500°C is given to be K. Of the
reactions given below, all at 1500°C, the reaction that has a
different equilibrium constant is
(a) at 5 atm
(b)2H 2 O 2 →2H 2 O at 1 atm
(c) at 2 atm
(d) at 5 atm
(e) at 1 atm
16–103 Of the reactions given below, the reaction whose
equilibrium composition at a specified temperature is not
affected by pressure is
(a)
(b)
(c)N 2 O 2 →2NO
(d)N 2 →2N
(e) all of the above.
16–104 Of the reactions given below, the reaction whose
number of moles of products increases by the addition of
inert gases into the reaction chamber at constant pressure and
temperature is
(a)
(b)
(c)N 2 O 2 →2NO
(d)N 2 →2N
(e) all of the above.
16–105 Moist air is heated to a very high temperature. If
the equilibrium composition consists of H 2 O, O 2 ,N 2 , OH,
H 2 , and NO, the number of equilibrium constant relations
needed to determine the equilibrium composition of the
mixture is
(a) 1 (b) 2 (c) 3 (d) 4 (e) 5
16–106 Propane C 3 H 8 is burned with air, and the combus-
tion products consist of CO 2 , CO, H 2 O, O 2 ,N 2 , OH, H 2 , and
NO. The number of equilibrium constant relations needed to
determine the equilibrium composition of the mixture is
(a) 1 (b) 2 (c) 3 (d) 4 (e) 5
16–107 Consider a gas mixture that consists of three com-
ponents. The number of independent variables that need to be
specified to fix the state of the mixture is
(a) 1 (b) 2 (c) 3 (d) 4 (e) 5CO^12 O 2 SCO 2H 2 ^12 O 2 SH 2 OCO^12 O 2 SCO 2H 2 ^12 O 2 SH 2 OH 2 ^12 O 2 3N 2 SH 2 O3N 2H 2 ^12 O 2 3N 2 SH 2 O3N 2H 2 O 2 SH 2 O^12 O 2H 2 ^12 O 2 SH 2 O1
2 O 2 SH 2 O822 | Thermodynamics16–108 The value of Henry’s constant for CO 2 gas dis-
solved in water at 290 K is 12.8 MPa. Consider water
exposed to atmospheric air at 100 kPa that contains 3 percent
CO 2 by volume. Under phase equilibrium conditions, the
mole fraction of CO 2 gas dissolved in water at 290 K is
(a) 2.3 10 ^4 (b) 3.0 10 ^4 (c) 0.80 10 ^4
(d) 2.2 10 ^4 (e) 5.6 10 ^4
16–109 The solubility of nitrogen gas in rubber at 25°C is
0.00156 kmol/m^3 · bar. When phase equilibrium is established,
the density of nitrogen in a rubber piece placed in a nitrogen
gas chamber at 800 kPa is
(a) 0.012 kg/m^3 (b) 0.35 kg/m^3 (c) 0.42 kg/m^3
(d) 0.56 kg/m^3 (e) 0.078 kg/m^3Design and Essay Problems
16–110 An article that appeared in the Reno Gazette-
Journalon May 18, 1992, quotes an inventor as saying that
he has turned water into motor vehicle fuel in a breakthrough
that would increase engine efficiency, save gasoline, and
reduce smog. There is also a picture of a car that the inventor
has modified to run on half water and half gasoline. The
inventor claims that sparks from catalytic poles in the con-
verted engine break down the water into oxygen and hydro-
gen, which is burned with the gasoline. He adds that
hydrogen has a higher energy density than carbon and the
high-energy density enables one to get more power. The
inventor states that the fuel efficiency of his car increased
from 20 mpg (miles per gallon) to more than 50 mpg of
gasoline as a result of conversion and notes that the conver-
sion has sharply reduced emissions of hydrocarbons, carbon
monoxide, and other exhaust pollutants.
Evaluate the claims made by the inventor, and write a
report that is to be submitted to a group of investors who are
considering financing this invention.
16–111 Automobiles are major emitters of air pollutants
such as NOx, CO, and hydrocarbons HC. Find out the legal
limits of these pollutants in your area, and estimate the total
amount of each pollutant, in kg, that would be produced in
your town if all the cars were emitting pollutants at the legal
limit. State your assumptions.cen84959_ch16.qxd 5/11/05 10:09 AM Page 822